Ammunition for high firing rate, light gas hypervelocity gun

ABSTRACT

Secondary ammunition for a high firing rate, light gas hypervelocity gun secondary ammunition having a hollow open inlet case containing a projectile. The gun has the primary and the secondary breech mechanisms spaced along a barrel containing a bore for successively transporting in unison to firing position, a primary ammunition round containing a propellent charge and a piston and a secondary ammunition piece, and means for introducing a gas under pressure into the bore between the breech mechanisms, whereby when the primary round is fired its piston is propelled forwardly through the bore to a terminal position within the secondary breech mechanism to compress the gas between the piston and the projectile of the secondary ammunition and thereby effect expulsion of the projectile from the gun at a hypervelocity. The piston and secondary ammunition core are from the gun during subsequent operation of the breech mechanisms to transport the next primary and secondary ammunition to firing position.

United States Patent [72] Inventor David Dal-dick Palos Verdes Estates, Calif. (21] Appl. No. 795,212 [22) Filed Jan. 30, 1969 Division of Ser. No. 664,882, Aug. 31,1967, Patent No. 3,496,828 [45] Patented Aug. 24, 1971 [73] Assignee TRW Inc.

Redondo Beach, Calif.

[54] AMMUNITION FOR HIGH FIRING RATE, LIGII GAS'HYPERVELOCII'Y GUN 2 Claims, 6 Drawing Figs.

[52] US. Cl 1112/92.], 102/38, 102/43 P, 102/93 [51] Int. Cl F42b 9/30 [50] Field of Search 102/38, 39, 93; 89/8 [56] References Cited UNITED STATES PATENTS 2,983,223 5/1961 Dardick 102/38 3,185,094 5/1965 Zehfeld 102/93 X 3,400,661 9/1968 Coon et al. 102/93 3,404,598 10/1968 Angelos 1 02/38 X 3,452,677 7/1969 Abela 102/93 X 1,395,630 11/1921 Davis 39/1 .701 2,979,991 4/1961 Buschers 89/1.5

Primary Examiner- Robert F. Stahl AttomeysDaniel T. Anderson, Gerald Singer and Alfons Valukonis ABSTRACT: Secondary ammunition for a high firing rate, light gas hypervelocity gun secondary ammunition having a hollow open inlet case containing a projectile. The gun has the primary and the secondary breech mechanisms spaced along a barrel containing a bore for successively transporting in unison to firing position, a primary ammunition round containing a propellent charge and a piston and a secondary ammunition piece, and means for introducing a gas under pressure into the bore between the breech mechanisms, whereby when the primary round is fired its piston is propelled forwardly through the bore to a terminal position within the secondary breech mechanism to compress the gas between the piston and the projectile of the secondary ammunition and thereby effect expulsion of the projectile from the gun at a hypervelocity. The piston and secondary ammunition core are from the gun during subsequent operation of the breech mechanisms to transport the next primary and secondary ammunition to firing position.

Patented Aug. 24, 1971 2 Sheets-Sheet 1 'l' 74 P" S 1111!!! ////////,7///////fl/////////////////////w/1 mvw'ron. David Dordick Patented Aug. 24, 1971 3,601,061

2 Sheets-Sheet 2 David Dordick ATTORNEY AMMUNITION FOR HIGH FIRING RATE, LIGHT GAS I HYPERVELOCITYGUN This application is adivision of my copending application Ser. No. 664,882, filed Aug. 31, 1967, now U.S. Pat. No. 3,496,827, and entitled High FIRING Rate, Light Gas Hypervelocity Gun and Ammunition Therefor.

- REFERENCE TO COPENDING APPLICATIONS Reference is made herein to copending applications Ser. No. 671,910, filed Sept; 1, 1967, now U.S. Pat. No. 3,446,113, and entitled, Sealed Open Chamber Breech Mechanism And Caseless Ammunition Therefor, and Ser. No. 665,136, filed Sept. 1, 1967 now U.S. Pat. No. 3,422,470, and entitled, Semicombustible Ammunition for Open Chamber Breech Mechanism."

BACKGROUND OF THE INVENTION i.e., hypervelocities. Such hypennuzzle velocities are achieved in various ways. The present invention is concerned with the particular hypervelocity gun technique which involves compression of a gas to an extremely high pressure within a bore between a propellant-driven piston and a releasably restrained projectile in the bore in such'manner as to effect abrupt release of the projectile and expulsion of the projectile from the bore at ahypervelocity by the pressure of the compressed gas. The existing hypervelocity guns of this kind, while capable of achieving hypermuzzle velocities, are deficient in that they. are tediousand time consuming to reload. As a consequence, such hypervelocity guns have never been adopted as a practical weapon.

My copending application, Ser. No. 664,882, provides an improvedlight gas, hypervelocity gun which avoids the abovenoted and other deficiencies of the eigisting guns of this type. The major advantage of my improved gun, for example, resides in its rapid reloading and'high firing rate capabilities. Generally speaking, my improved gun is characterized by primary and secondary breech mechanisms spaced along a barrel containing a bore. The primary breech mechanism is arranged to receive and successively transport to firing position in the breech mechanism primary ammunition rounds each containing a piston and a propellant charge. Each primary round, when in firing position, is coaxially aligned with the breech end of the bore. When a primary round is fired, its piston is propelled forwardly at high velocity through the bore by propellant gas pressure. The secondary breech mechanism is arranged to receive and successively transport to firing position in the breech mechanism secondary ammunition rounds each containing a projectile. The projectile of each secondary round, when in firing position, is coaxially'disposed within and is releasably restrained against forward movement through the bore. The gun is also equipped with means for introducing a gas under pressure into the bore between the breech mechanisms.

In firing operation of the gun, the breech mechanisms are operated in unison to simultaneously transport primary and secondary ammunition rounds to firing position. A charge of compressed gas is then introduced into the bore between the breech mechanisms, after which the primary round is fired to effect forward propulsion of its piston through the bore to a terminal position in the secondary breech mechanism. As the piston travels through the bore, the gas in the bore is compressed to extremely high pressure between the piston and the releasably restrained projectile of the secondary ammunition round currently in firing position. As the piston approaches its terminal position within the secondary breech mechanism, the projectile is abruptly released and driven forwardly through the bore at a hypervelocity by the highly compressed gas between the projectile and the piston. The piston of'the fired primary round lodges within the secondary breech mechanism and is ejected from the gun during subsequent operation of the breech mechanisms to transport the nextprimary and secondary rounds to firing position.

The hypervelocity gun may employ either closed chamber or open chamber breech actions. or both closed and open chamber breech actions in various combinations. In this regard, it should be noted that a closed chamber breech action is one in which each ammunition round is inserted or rammed axially into'a circumferentially closed firing chamber through one end of the chamber and the spent cartridge case of each fired round is extracted axially from the chamber. Examples of this type of breech mechanism are the conventional belt or clip fed mechanisms, the revolver mechanism, the Gatling mechanism, and the separate chamber mechanism. An open chamber breech action, on the other hand, is one in which each ammunition round is introduced laterally into a firing chamber through an open side of the chamber and the spent cartridge case of each fired round is ejected laterally through the open side of the chamber. Examples of such open chamber breech mechanisms are those disclosed in prior art U.S. Pat. Nos.: 2,983,223; 3,041,938; 2,831,140; 2,847,784; and 3,044,890.

SUMMARY OF THE INVENTION The present invention provides novel secondary ammuni tion for the hypervelocity gun described above. The secondary ammunition has a hollow open-ended case containing a projectile to be propelled forwardly through the bore by the compressed gas and means for receiving the piston of the fired primary round to permit ejection of the piston from the secondary breech mechanism, in the manner explained earlier. As will be seen presently, the secondary ammunition may comprise fully cased open chamber ammunition having a case similar to that disclosed in the aforementioned prior art patents or semicombustible ammunition having a skeletonized cartridge case similar to that disclosed in the copending application entitled, Semicombustible Ammunition for Open Chamber Breech Mechanism.

BRIEF DESCRIPTION OF THE DRAWING In the drawing: I

FIG. I is a perspective view of an open chamber hypervelocity gun for firing the present ammunition;

FIG. 2 is an enlarged fragmentary side elevation of the gun with parts sectioned for clarity of illustration;

FIG. 3 is a section taken on line 33 in FIG. 2;

FIG. 4 is an enlarged longitudinal section through the present secondary ammunition;

FIG. 5 is a section taken on line 55 in FIG. 4; and

FIG. 6 is an enlarged fragmentary section showing the piston of a fired primary ammunition round in its terminal position within the secondary breech mechanism of the gun. DESCRIPTION OF THE PREFERRED EMBODIMENTS The illustrated hypervelocity gun It) is identical to that disclosed in my copending application Ser. No. 664,882, and has a barrel 12 containing a bore 14. Spaced along the barrel are a pair of open chamber breech mechanisms 16 and 18. Breech mechanism 16 is located at the breech end of the barrel and is hereinafter referred to as a primary breech mechanism. Breech mechanism 18, hereinafter referred to as a primary breech secondary breech mechanism, is located forwardly along the barrel from the primary breech mechanism. Primary breech mechanism 16 has a breech frame 20 supporting a rotary ammunition carrier or cylinder 26 containing generally triangular firing chambers 28 which open laterally through the cylinder circumference 28. Carrier 26 is rotatable to locate its firing chambers successively in an ammunition infeed position, a firing position, and an ejection position. When in infeed position, each chamber is disposed to receive a primary ammunition round to be fired. When in firing position, each firing chamber 28 is coaxially disposed relative to and opens forwardly to the breech end of the gun bore 14. Finally, when in ejection position, each chamber is disposed for ejection of the spent cartridge case of a cased primary round from the firing chamber after firing. The secondary breech mechanism 18 is essentially identical except for size to the primary breech mechanism 16. For this reason, the parts of the secondary breech mechanism are referred to by the same reference numerals, with a prime subscript, as the corresponding parts of the primary breech mechanism. For reasons which will appear as the description proceeds, the chambers 28 in the secondary breech carrier or cylinder are 26' referred to as an ammunition chambers rather than firing chambers, as is the chamber in the primary breech carrier. The secondary breech carrier 26', like the primary breech carrier 26, is rotatable to locate its ammunition chambers 28' successively in an ammunition infeed position, a firing position, and an ejection position. When in infeed position, the ammunition chamber is disposed to receive secondary ammunition to be fired. When in firing position, each ammunition chamber is coaxially disposed relative to and opens forwardly and rearwardly to the gun bore 14. Finally, when in ejection position, each ammunition chamber is disposed for ejection of the outer case of the secondary ammunition from the ammunition chamber after firing. Drive means 30 are provided for driving the two breech carriers 26, 26' in unison to their infeed, firing, and ejection positions. Communicating with the gun bore 14, between the primary and secondary breech mechanisms 16, 18, are pressurizing means 31 for introducing a gas, such as hydrogen or helium, into the gun bore.

The primary breech mechanism 16 operates to transport primary ammunition rounds 32 in succession to firing position in the primary breech mechanism and to fire each primary round in this position. Each illustrated primary round comprises a yieldable, noncombustible cartridge case 34 containing a forward piston 36, a rear propellant charge 28, and a primer 39. The secondary breech mechanism 18 operates to transport the secondary ammunition 40 in succession to firing position within the secondary breech mechanism. Each illustrated piece of secondary ammunition comprises a yieldable, noncombustible sleevelike case 42 having a central longitudinally continuous bore 48 containing a forward projectile 44 and a projectile-restraining sleeve 46. The secondary ammunition 40 constitute the subject matter of the present invention and will be described in greater detail presently. It is significant to note here, however, that while the illustrated secondary ammunition is fully cased ammunition, the ammunition may comprise semicombustible similar to that disclosed in the aforementioned copending application, Ser. No. 665,136.

Briefly, in operation of the hypervelocity gun 10, the ammunition carriers 26, 26' of the primary and secondary breech mechanisms 16, 18 are first driven to infeed position. A primary ammunition round 32 is then introduced into the firing chamber 28 of the primary carrier and a piece of secondary ammunition 40 is introduced into the ammunition chamber 28' of the secondary carrier. Thereafter, the carriers are driven to firing position and the pressurizing means 31 are actuated to admit a charge of gas under pressure into the gun bore 14 between the breech mechanisms. At this point, the primary round 32 currently in firing position is fired by actuation of the primary breech firing means 50. The piston 36 of the fired primary round is the propelled forwardly at high velocity through the gun bore by the high-pressure propellant gas generated by firing of the primary round. The piston travels forwardly through the bore to a terminal position within the secondary breech mechanism 18, wherein the piston lodges within the bore 48 of the secondary ammunition 40 currently in firing position. As the piston of the fired primary round travels forwardly through the gun bore 14 to its terminal position in the secondary breech mechanism, the gas introduced into the gun bore prior to firing is compressed to an extremely high pressure between the piston and the projectile 44 of the secondary 40 currently in firing position. The projectile is restrained, by the projectile-restraining sleeve 46 of the secondary ammunition, against forward movement through the gun bore until the piston 36 of the fired primary round approaches its terminal position. The projectile is then abruptly released and propelled forwardly through the gun bore at hypervelocity by the pressure of the highly compressed gas between the piston and projectile. After firing, the ammunition carriers 26, 26 are driven to ejection position to eject the spent cases 34, 42 of the fired primary and secondary ammunition 32 40. The piston 36 of the fired primary round, which is then lodged within the spent case 42 of the fired secondary ammunition, is ejected with the latter case.

As noted earlier, each primary ammunition round 32 has a cartridge case 34 containing a piston 36 which is sized to fit slidably in the rear portion of the gun bore 14, a propellant charge 38 for propelling the piston forwardly to the bore, and a primer 39 for igniting the propellant. Each piece of ammunition secondary sleevelike has a case 42 havina a central longitudinally Each piece of secondary ammunition sleevelike has a case 42 having a central longitudinally continuous base 48 and Each piece of secondary ammunition has a sleevelike case 42 having a central longitudinally continuous bore 48 and containing a projectile 44 and a projectile-restraining sleeve 46. Bore 48 is sized to receive the piston 36 of a primary round. The ammunition cases 34, 42 are sized triangularly shaped to complement the primary and secondary cylinder chambers 28, 28' in the manner explained earlier. The primary ammunition pistons 36 are preferably hollow as shown to maximize the propellant space in the primary rounds 32, and are provided with external sealing means for sealing the pistons to the wall of the gun bore 14. Each piston is frictionally retained in its cartridge case 34 to permit feeding of the primary ammunition rounds to the gun without separation of the pistons from their cartridge cases. The projectilerestraining sleeve 46 of the secondary ammunition 40 is frictionally fitted within the bore 48 of the ammunition case 42 and is constructed of a relatively hard metal. The external diameter of the sleeve is substantially greater than the diameter of the forward portion of the gun bore 14. Accordingly, when a piece of secondary ammunition is located in firing position within the secondary breech mechanism 18, the forward end of its restraining sleeve seats against the rear end of the front barrel section 12a. The central opening in the restraining sleeve has a uniform diameter at its forward end, which is the same as that of the forward portion of the gun bore 14. The rear end of the sleeve opening flares outwardly to a larger diameter, as shown, to form a rearwardly presented shoulder about the rear end of the sleeve opening. The projectile 44 of the secondary ammunition has a forward end which fits closely within the uniform diameter portion of the central opening through its respective restraining sleeve 46. The rear end of the projectile flares outwardly to complement the flaring rear end of the sleeve opening and form a deformable lip engaging the shoulder.

It is now evident, therefore, that when secondary ammunition 40 is located in firing position in the secondary breech mechanism 18, its projectile 44 is restrained against forward movement through the restraining sleeve 46. The rear ends of the projectile 44 and projectile restraining sleeve 46 are spaced from the rear end of the case a distance equal to or slightly greater than the length of each primary ammunition piston 36.

The pressurizing means 31 of the gun 10 for supplying gas under pressure to the rear portion of the gun bore 14 between the primary and secondary breech mechanisms 16, 18 comprise a pressure vessel or tank 68 for containing a supply of light gas, such as hydrogen or helium under pressure. Between the tank and the rear barrel section 12b is a valve 70. This valve has an inlet which communicates to the interior of the tank and an outlet which communicates to the rear portion of the gun bore 14 between the primary and secondary breech mechanisms 16, 18. Valve 70 is normally closed, and is periodically opened to admit a charge of gas under pressure into the gun bore 14 in timed relation to rotation of the breech cylinders 26, 26' from one firing position to the next.

During operation of the hypervelocity gun 10, the primary and secondary breech cylinders 26, 26' are driven in such a way that the cylinder chambers 28, 28 are rotated in sequence to and momentarily arrested in their infeed firing and ejection positions. As each cylinder chamber rotates to infeed position, it receives primary or secondary ammunition 32 or 40 from its ammunition hopper 64 or 66, as the case may be, after which the ammunition rotates with its containing chamber to firing position.

Immediately following arrival of the primary and secondary ammunition 32, 40 in firing position, the valve 70 is momentarily opened to admit a charge of gas under pressure to the gun bore 14 between the breech mechanisms 16, 18. The firing'means 50 is then actuated to fire the primary ammunition round 32 currently in firing position. Firing of the primary round results in propulsion of its piston 36 forwardly at high velocity through the gun bore 14 to its terminal position within the secondary breech mechanism 18. In this terminal position, the piston is contained within the rear end of the bore 48 of the secondary ammunition 40 currently in firing position. As the piston travels forwardly through the gun bore toward its terminal position, the initially pressurized gas is compressed between the piston and the restrained projectile 44 of the secondary ammunition. The gas is thus compressed to a pressure on the order of 60,000 to 80,000 p.s.i. as the piston approaches its terminal position within the secondary breech mechanism.

The projectile 44 of the secondary ammunition 40 in firing position is restrained by its restraining sleeve 46 until the compressed gas in the gun bore 14 behind the projectile has attained the desired high pressure. This high pressure is then effective to force or extrude the projectile through its restraining sleeve and to thereafter propel the projectile forwardly through the forward barrel section 12a at hypervelocity.

The rate of intermittent rotation of the breech cylinders 26, 26' is such that the cylinders are driven from one firing position to the next after evacuation of the gun bore 14 has occurred following the previous firing. New primary ammunition 32 and secondary ammunition 40 are thereby rotated to firing position, and the above described firing sequence is repeated. This rotation of the breech cylinders also transports the spent cases, 34, 42 of the previously fired primary and secondary ammunition from firing position to ejection position, wherein the cases are ejected from their respective cylinder chambers 28, 28. The piston 36 of the previously fired primary round 32, which is now lodged within the spent case of the secondary ammunition 40, is ejected with the latter case.

What is claimed as new in support of Letters Patent is:

1. Secondary ammunition for a hypervelocity gun of the character described, comprising:

an outer sleevelike case having a central longitudinally continuous bore opening through the front and rear ends of said sleeve;

a projectile within the front end of said bore adapted to be propelled forwardly from said bore by pressurizing with gas the portion of said bore behind said projectile;

projectile-restraining means within the forward end of said bore for releasably restraining said projectile against forward movement from said bore;

said projectile-restraining means comprising a restraining sleeve having a central opening receiving said projectile and defining a rearwardly presented shoulder about the rear end of said sleeve opening; and

the rear end of said projectile having a deformable lip engaging said shoulder to releasably restrain said projectile against forward movement through said sleeve opening.

2. Secondary ammunition for a hypervelocity gun of the character described, comprising:

an outer sleevellke case having a central longitudinally continuous bore opening through the front and rear ends of said sleeve;

a projectile within the front end of said bore adapted to be propelled forwardly from said bore by pressurizing with gas the portion of said bore behind said projectile; and

said case having a generally triangular shape in transverse cross section and convex cylindrically curved sides of equal radii, whereby said ammunition is adapted to be fired in an open chamber breech mechanism. 

1. Secondary ammunition for a hypervelocity gun of the character described, comprising: an outer sleevelike case having a central longitudinally continuous bore opening through the front and rear ends of said sleeve; a projectile within the front end of said bore adapted to be propelled forwardly from said bore by pressurizing with gas the portion of said bore behind said projectile; projectile-restraining means within the forward end of said bore for releasably restraining said projectile against forward movement from said bore; said projectile-restraining means comprising a restraining sleeve having a central opening receiving said projectile and defining a rearwardly presented shoulder about the rear end of said sleeve opening; and the rear end of said projectile having a deformable lip engaging said shoulder to releasably restrain said projectile against forward movement through said sleeve opening.
 2. Secondary ammunition for a hypervelocity gun of the character described, comprising: an outer sleevelike case having a central longitudinally continuous bore opening through the front and rear ends of said sleeve; a projectile within the front end of said bore adapted to be propelled forwardly from said bore by pressurizing with gas the portion of said bore behind said projectile; and said case having a generally triangular shape in transverse cross section and convex cylindrically curved sides of equal radii, whereby said ammunition is adapted to be fired in an open chamber breech mechanism. 